Sebastian Naranjo

2019 REU Student | Jariwala Lab

Sebastian Naranjo is a rising senior from Rowan University, NJ. He is working in Dr. Deep Jariwala’s lab, studying the direct identification of mesenchymal stem cell mechanisms in the presence of a dynamic graphene based electrical field. Sebastian is from Kinnelon, NJ, and hopes to complete a PhD in efforts to one day conduct independent and cutting-edge cancer research.

Research Abstract:

Graphene-Based Microdevices to Probe Effects of Electrical Stimulation on Stem Cell Behavior

Graphene monolayer has been shown to not only promote hMSC adhesion, but also accelerated and controlled osteogenesis. In the presence of an applied voltage, the graphene and the Si substrate behave as capacitor plates while the SiO2 behaves as a dielectric. The 2D material (graphene) behaves as a leaky capacitor plate. The electrical field that penetrates through the graphene monolayer is easily modulated to produce an electrical stimulus that spans approximately 20 nm, giving the induced electrical field the capability to specifically probe cell transmembrane receptor-ECM binding junctions. Epoxy resin was used to seal off all device circuitry from the cell culture, leaving only the graphene monolayer in contact with the cell culture. Microwells were then manufacture by placing pieces of PDMS on top of the epoxy resin. A 170 mV/mm electrical field was generated using a wave function generator and determined to be far too high and resultant in cell death. However, preliminary results indicate that graphene promotes cell spreading compared to the polystyrene petri dish after overnight incubation. Enhanced migration and proliferation were also observed with the on the chip that was incubated the entire duration of the experiment compared to the petri dish. However, cells that were seeded in the PDMS microwells died due to excess drying. Graphene has been shown to accelerate a spindle shaped cytoskeleton and aggregation was also qualitatively and statistically observed throughout preliminary, but more elaborate immunostaining is necessary to confirm this phenomenon.